Such linear sensors are used in motor vehicle technology, for example, for controlling brake boosters, the activation of which is carried out as a function of the travel of a brake pedal. As the pedal travel increases, the brake pressure acting on a control member is increased, the travel of which can be determined by way of a linear sensor. Another example is boost-pressure controllers for exhaust gas turbochargers. In such applications, in general the pin of the linear sensor is pressed against a movable measurement object, such as a control member, by a spring force, so that the pin always rests against the measurement object and follows the movement thereof.
A linear sensor is known from DE 196 24 233 C1, wherein a cuboid permanent magnet is displaced relative to a magnetic field sensor disposed in a stationary manner on a housing. The known linear sensor, however, is less suited for applications in motor vehicle technology, because it responds sensitively to vibrations which may develop due to engine operation, is prone to wear, and requires high manufacturing costs and frequent adjustments.
DE 197 51 519 C2 describes a linear sensor, for example for controlling a brake booster for generating an electric control signal as a function of the relative position of two parts displaceable relative to each other, wherein the linear sensor has a magnet, with which at least one Hall sensor is associated, wherein the magnet and the Hall sensor are held such that they can be displaced relative to each other and the Hall sensor supplies an electric voltage signal that is dependent on the position of the sensor relative to the magnet, wherein the magnet is fixed non-displaceably in a housing of the linear sensor and the Hall sensor can be displaced relative to the magnet in the housing.